K.B.
I would think hard candy that he can share, little bars of travel soap, shampoo that he can share. As for things for himself: nuts, pretzels, hot chocolate packets, mini marshmallows, biscotti (would hold up to the six weeks of shipping), travel wipes for quick clean ups, hand sanitizer, new socks, shoe inserts, anything to make his work easier would be a huge gift to him.